The FreeBSD Ports
Collection is a collection of software with a standard means
of compilation and installation. FreeBSD is a source distribution
(whereas Debian is a Binary Distribution). Packages come in
source-code form with a Makefile suitable for installing the program
on a FreeBSD system. The ports collection is very large (around 9000
packages).

Some things may be simpler with a source distribution than with
a binary distribution. For instance, since the code is expected to be
already on the machine and buildable, when a new compiler is installed
one merely needs to rebuild the dependant libraries. In contrast,
with a binary distribution like Debian one must wait for a new binary
package to be made available. However, as I understand it, FreeBSD
has no means of recompiling dependant packages automatically when a
new compiler is installed.